Which variable is adjusted automatically when using an automatic exposure control (AEC)?

When using an automatic exposure control (AEC) system, the exposure time is the variable that is automatically adjusted. AEC is designed to optimize the amount of radiation used to produce an x-ray image by monitoring the radiation that reaches the detector. When sufficient radiation has been detected to create a diagnostic-quality image, the AEC system terminates the exposure.

This automatic adjustment helps to ensure consistent image quality while minimizing patient radiation dose. By maintaining appropriate exposure time based on the density of the area being imaged, AEC contributes to the efficiency of the x-ray process, allowing for rapid and reliable imaging without requiring manual calculations for each exposure.

In contrast, while mA (milliamperage) and kVp (kilovolt peak) are crucial parameters in x-ray imaging, they are typically set manually by the operator before the procedure begins and do not change automatically when using AEC. Rectification relates to the conversion of alternating current to direct current in x-ray generators and is not a variable affected by AEC.